From cluster calculations to molecular materials: a mixed pseudopotential approach to modeling mixed-valence systems.

In this paper we present a technique for finding an appropriate parameterization of ultrasoft pseudopotentials for modeling mixed-valence materials. For the example of hexacyanometallate molecular building blocks, we show how ionic cluster calculations can be used to determine a set of parameters for the metal centers. Pseudopotentials chosen in such a way are then shown to be suitable for periodic calculations of the corresponding mixed-valence materials (e.g., Prussian Blue).